Three opposition leaders are due in court after being forcibly detained along with hundreds of other protesters who rallied in central Moscow to question the legitimacy of Prime Minister Vladimir Putin's election to a third term as the country's president.

Opposition leaders Sergei Udaltsov, Ilya Yashin, and Aleksei Navalny -- along with other detainees -- have since been released but were scheduled to appear in court on March 6 to face charges connected with the protest.

Navalny and Udaltsov were reportedly charged with administrative offenses and faced fines of up to 2,000 rubles (some $70) each. Yashin was charged with violations over the holding of the rally and faced up to 15 days in jail.

Police detained some 250 people in Moscow, and another 300 in St. Petersburg, at another anti-Putin protest.

According to official results of the March 4 election, Putin, the current prime minister, won a third mandate as president, taking some 64 percent of the vote in a landslide victory.

WATCH: Riot police detained dozens of people after thousands of protesters took to the streets of Moscow to challenge Vladimir Putin's victory in the March 4 presidential election. (Video by RFE/RL's Russian Service)